This invention relates to a jig for use in assembling a toroidal continuously variable transmission.
A toroidal type continuously variable transmission (toroidal CVT) transmits a rotation torque by power rollers gripped between an input disk and output disk, and achieves a desired speed ratio according to a gyration angle of the power rollers.
The input disk and the output disk rotate around a relatively long shaft member known as a CVT shaft. When the toroidal continuously variable transmission is assembled, an output disk is fitted in a housing. The CVT shaft penetrates a hole formed in the center of the output disk, and the input disk is then fitted to the CVT shaft.
In a xe2x80x9cdouble cavityxe2x80x9d CVT wherein two input disks and output disks are arranged on the same CVT shaft, the two output disks are first fitted to the housing. The CVT shaft to the base end of which one input disk is attached, is passed through the output disks, and the other input disk is fitted on the penetrating end.
As various members are fitted to the CVT shaft, the diameter of the CVT shaft is not uniform, and in some parts of the shaft, there are large diameter parts and small diameter parts separated by a step. When the CVT shaft is passed through the output disk and other members during assembly of the continuously variable transmission, these steps may catch in the holes of the parts which renders assembly of the CVT difficult.
It is therefore an object of this invention to facilitate the operation of passing the CVT shaft through the output disk which is required for assembly of the toroidal continuously variable transmission.
In order to achieve the above object, this invention provides a jig for passing an axial member of a continuously variable transmission through disks which have been prefitted in a housing, wherein the axial member has a step between a large diameter part and a small diameter part. The jig comprises a sheath member which fits on the outer circumference of the small diameter part adjacent to the step, the outer diameter of the sheath member gradually decreasing from an outer diameter equal to that of the large diameter part.
This invention also provides a method of assembling a toroidal continuously variable transmission that has an axial member passing through disks which have been prefitted in a housing, wherein the axial member has a step between a large diameter part and a small diameter part. The method comprises passing the axial member through the disks after fitting a sheath member having an outer diameter which gradually decreases from an outer diameter equal to that of the large diameter part onto the small diameter part of the member.
The details as well as other features and advantages of this invention are set forth in the remainder of the specification and are shown in the accompanying drawings.